Fix checking of declared exceptions for methods in parent classes (#2547

)

In case when parent contains throws keyword on its method and child overrides this method removing throws, it should be possible to mock throwing exception from child.

Fixes #2201

Co-authored-by: Andrey Kozel <andrey.kozel@kaseya.com>

src/main/java/org/mockito/internal/stubbing/answers/InvocationInfo.java

@@ -6,6 +6,9 @@
 
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 
 import org.mockito.internal.invocation.AbstractAwareMethod;
 import org.mockito.internal.util.MockUtil;
@@ -24,15 +27,52 @@ public InvocationInfo(InvocationOnMock theInvocation) {
         this.invocation = theInvocation;
     }
 
-    public boolean isValidException(Throwable throwable) {
-        Class<?>[] exceptions = method.getExceptionTypes();
-        Class<?> throwableClass = throwable.getClass();
-        for (Class<?> exception : exceptions) {
+    public boolean isValidException(final Throwable throwable) {
+        if (isValidException(method, throwable)) {
+            return true;
+        }
+
+        return isValidExceptionForParents(method.getDeclaringClass(), throwable);
+    }
+
+    private boolean isValidExceptionForParents(final Class<?> parent, final Throwable throwable) {
+        final List<Class<?>> ancestors = new ArrayList<>(Arrays.asList(parent.getInterfaces()));
+
+        if (parent.getSuperclass() != null) {
+            ancestors.add(parent.getSuperclass());
+        }
+
+        final boolean validException =
+                ancestors.stream()
+                        .anyMatch(ancestor -> isValidExceptionForClass(ancestor, throwable));
+
+        if (validException) {
+            return true;
+        }
+
+        return ancestors.stream()
+                .anyMatch(ancestor -> isValidExceptionForParents(ancestor, throwable));
+    }
+
+    private boolean isValidExceptionForClass(final Class<?> parent, final Throwable throwable) {
+        try {
+            final Method parentMethod =
+                    parent.getMethod(this.method.getName(), this.method.getParameterTypes());
+            return isValidException(parentMethod, throwable);
+        } catch (NoSuchMethodException e) {
+            // ignore interfaces that doesn't have such a method
+            return false;
+        }
+    }
+
+    private boolean isValidException(final Method method, final Throwable throwable) {
+        final Class<?>[] exceptions = method.getExceptionTypes();
+        final Class<?> throwableClass = throwable.getClass();
+        for (final Class<?> exception : exceptions) {
             if (exception.isAssignableFrom(throwableClass)) {
                 return true;
             }
         }
-
         return false;
     }
 

src/test/java/org/mockito/internal/invocation/InvocationBuilder.java

@@ -30,6 +30,7 @@ public class InvocationBuilder {
     private int sequenceNumber = 0;
     private Object[] args = new Object[] {};
     private Object mock = Mockito.mock(IMethods.class);
+    private Class<?> mockClass = IMethods.class;
     private Method method;
     private boolean verified;
     private List<Class<?>> argTypes;
@@ -57,7 +58,7 @@ public Invocation toInvocation() {
 
             try {
                 method =
-                        IMethods.class.getMethod(
+                        mockClass.getMethod(
                                 methodName, argTypes.toArray(new Class[argTypes.size()]));
             } catch (Exception e) {
                 throw new RuntimeException(
@@ -115,6 +116,12 @@ public InvocationBuilder mock(Object mock) {
         return this;
     }
 
+    public InvocationBuilder mockClass(Class<?> mockClass) {
+        this.mockClass = mockClass;
+        this.mock = mock(mockClass);
+        return this;
+    }
+
     public InvocationBuilder method(Method method) {
         this.method = method;
         return this;

src/test/java/org/mockito/internal/stubbing/answers/InvocationInfoExceptionTest.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2022 Mockito contributors
+ * This program is made available under the terms of the MIT License.
+ */
+package org.mockito.internal.stubbing.answers;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.mockito.internal.invocation.InvocationBuilder;
+import org.mockito.invocation.Invocation;
+
+import java.nio.charset.CharacterCodingException;
+import java.util.Arrays;
+import java.util.Collection;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(Parameterized.class)
+public class InvocationInfoExceptionTest {
+
+    private final String methodName;
+
+    public InvocationInfoExceptionTest(final String methodName) {
+        this.methodName = methodName;
+    }
+
+    @Parameterized.Parameters
+    public static Collection<Object[]> data() {
+        return Arrays.asList(
+                new Object[][] {
+                    {"throwException"},
+                    {"parentThrowsException"},
+                    {"grandParentThrowsException"},
+                    {"interfaceThrowsException"},
+                    {"grandInterfaceThrowsException"},
+                    {"interfaceOfParentThrowsException"}
+                });
+    }
+
+    @Test
+    public void should_know_valid_throwables() throws Exception {
+        // when
+        final Invocation invocation =
+                new InvocationBuilder()
+                        .method(methodName)
+                        .mockClass(CurrentClass.class)
+                        .toInvocation();
+        final InvocationInfo info = new InvocationInfo(invocation);
+
+        // then
+        assertThat(info.isValidException(new Exception())).isFalse();
+        assertThat(info.isValidException(new CharacterCodingException())).isTrue();
+    }
+
+    private abstract static class GrandParent {
+        public abstract void grandParentThrowsException() throws CharacterCodingException;
+    }
+
+    private interface InterfaceOfParent {
+        abstract void interfaceOfParentThrowsException() throws CharacterCodingException;
+    }
+
+    private abstract static class Parent extends GrandParent implements InterfaceOfParent {
+        public abstract void parentThrowsException() throws CharacterCodingException;
+    }
+
+    private interface GrandInterface {
+        void grandInterfaceThrowsException() throws CharacterCodingException;
+    }
+
+    private interface Interface extends GrandInterface {
+        void interfaceThrowsException() throws CharacterCodingException;
+    }
+
+    private static class CurrentClass extends Parent implements Interface {
+
+        public void throwException() throws CharacterCodingException {}
+
+        @Override
+        public void grandParentThrowsException() {}
+
+        @Override
+        public void parentThrowsException() {}
+
+        @Override
+        public void grandInterfaceThrowsException() {}
+
+        @Override
+        public void interfaceThrowsException() {}
+
+        @Override
+        public void interfaceOfParentThrowsException() {}
+    }
+}

src/test/java/org/mockito/internal/stubbing/answers/InvocationInfoTest.java

@@ -9,26 +9,13 @@
 import static org.mockitoutil.TestBase.getLastInvocation;
 
 import java.lang.reflect.Method;
-import java.nio.charset.CharacterCodingException;
 
 import org.junit.Test;
 import org.mockito.internal.invocation.InvocationBuilder;
-import org.mockito.invocation.Invocation;
 import org.mockitousage.IMethods;
 
 public class InvocationInfoTest {
 
-    @Test
-    public void should_know_valid_throwables() throws Exception {
-        // when
-        Invocation invocation = new InvocationBuilder().method("canThrowException").toInvocation();
-        InvocationInfo info = new InvocationInfo(invocation);
-
-        // then
-        assertThat(info.isValidException(new Exception())).isFalse();
-        assertThat(info.isValidException(new CharacterCodingException())).isTrue();
-    }
-
     @Test
     public void should_know_valid_return_types() throws Exception {
         assertThat(